hi folks, i'm doing a bit of research for an upcoming project and any suggestions would be welcome.
The director would like to replace stand in actors heads with some cg heads, and i'm looking for the best way to go about doing this. the camera will most likely be moving and motion control isn't an option, the actors will of course be moving to. I've been investigating some sort of rig with ping pong balls (or similar) and then possibly syntheyes or boujou to track and send to maya. the shot would later be comped in shake / nuke / afx. however i haven't been having much success. the biggest problem(s) are that the actors will likely be doing some fairly extreme motions, turning full 360 deg. and that it's supposed to be a night shot, with flares, so there goes the day for night option.
if anybody has had to do this sort of thing before or has any suggestions please feel free to post them.
thanks.
s

with this, i would probably do a full 3D track. reason is because you will always have to worry about head rotation in zspace. this is probably one of the hardest tracks to do haha, but it is possible if you take it step by step in your head and make sure it works before you do it.

so far here's what i've figured out for those who are interested.
run the footage through syntheyes (or boujou) and get back the camera move, make sure to remove lens distortions first.
try too track points (on shoulders and torso, turns out neck and head aren't all that important) and use those points as a guide to manually track a virtual replica of the physical rig onto the actors. things to remember, never scale the rig, only rotate and move. have notes on the lens used distance to actors, fstop and aperture. sacrifice at least three animals to the gods of compositing. pray. if this fails, murder all involved and bury the evidence.

well try just tracking the 3D track of the scene first and then just have the cg artist match rotations. this way all you have to do is do a 2D track transform for position and scale in shake. that is probably the best answer i have. if this fails then i say sacrifice a few animals to the gods of compositing.